| SAS/ACCESS Interface to IMS-DL/I: Reference |
The SAS/ACCESS interface
to IMS-DL/I is different from other SAS/ACCESS interfaces
in that it requires you to define the database in your access descriptor.
Other SAS/ACCESS interfaces are able
to query a data dictionary or other information repository to acquire detailed
information about the database object that is being accessed.
Defining access descriptors for IMS-DL/I databases can
be time consuming because the data have to be entered manually. To automate
this process, especially in cases where many access descriptors must be defined,
there are several tools available for your use.
The
COB2SAS tool uses the
COB2SAS utility to process COBOL copybook database definitions and to store
them in a permanent SAS data file. This data file is then processed by a
DATA step program that is supplied in the installed prefix.SAMPLE
PDS, called IMSS2A. The IMSS2A program processes the observations in the
data file and generates most of the syntax required by the PROC ACCESS procedure
statements that create an access descriptor for the database.
The generated statements are written to a host file
(physical sequential or PDS member) where they can be edited. The statements
written to the host file require some editing because the copybook file does
not contain all the information that is necessary to create the access descriptor.
You need to add DBD-specific information such as segment lengths, search
and sequence field names, DBD name, DBTYPE, and segment names, in order to
complete the code. You can then either submit the generated statements with
JCL in a batch execution, or submit them from the SAS PROGRAM EDITOR window.
The COB2SAS tool is available from SAS Institute free
of charge for download from the World Wide Web, from an FTP site, or in the
form of a mailer tape. This tool was originally designed to aid in converting
COBOL file copybooks to INPUT statements for SAS DATA steps. For access descriptor
creation, it is not necessary to complete all of the steps outlined in the
COB2SAS usage instructions. Typically, after the copybook is processed, the
results are stored in a temporary SAS file, which is then used to generate
the INPUT statement. For IMS-DL/I access descriptor creation, only the steps
up to and including creation of the SAS file (dictionary file) are necessary.
A modification is made to make the dictionary file permanent, and from there
the IMSS2A program is used to complete the process.
Note that only steps R2COB1-R2COB5 are needed to create
the dictionary file. Member R2MVS is the file to edit to make the dictionary
a permanent file. R2MVS is also the main program that drives all of the other
steps. It is well documented, and comments provide information on what each
step does.
For more information about using the COB2SAS tool and
about the IMSS2A sample program, call SAS Institute's Technical Support Division.
The second tool was donated by a SAS user.(footnote 1)
The tool consists of SAS macro and DATA step code that processes
the database DBD directly. The benefit of this tool is that the file of generated
PROC ACCESS code does not need further editing before being submitted for
execution. This tool is available by request from SAS Institute's Technical
Support Division.
FOOTNOTE 1:
Bruce
Babbitt of New England Power Service Company ![[arrow]](../common/images/fntarrow.gif)
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
